One way to store and process the three-dimensional sound field of spherical microphone arrays is the Higher-Order Ambisonics (HOA) representation. Ambisonics uses orthonormal spherical functions for describing the sound field in the area around and at the point of origin, or the reference point in space, also known as the sweet spot. The accuracy of such description is determined by the Ambisonics order N, where a finite number of Ambisonics coefficients are describing the sound field. The maximum Ambisonics order of a spherical array is limited by the number of microphone capsules, which number must be equal to or greater than the number O=(N+1)2 of Ambisonics coefficients.
An advantage of such Ambisonics representation is that the reproduction of the sound field can be adapted individually to nearly any given loudspeaker position arrangement.